LeetCode 21. Merge Two Sorted Lists

分析

难度：易

题目

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

Example:

Input: 1->2->4, 1->3->4

Output: 1->1->2->3->4->4

解答

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package LeetCode;   public class L21_MergeTwoSortedLists {     public ListNode mergeTwoLists(ListNode l1, ListNode l2) {         ListNode temp=new ListNode(0);//指示当前节点         ListNode ln=temp;//ln为链表头部，返回的链表头部加入了一个节点。         while(l1!=null &&l2!=null)         {             if(l1.val>l2.val){                 temp.next=l2;                 l2=l2.next;             }             else{                 temp.next=l1;                 l1=l1.next;             }             temp=temp.next;//注意链表上的移动，         }         if(l1!=null){             temp.next=l1;         }else         {             temp.next=l2;         }         return ln.next;     } }